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1.
Tamaura Y 《Ambio》2012,41(Z2):108-111
When a concentrated solar beam is irradiated to the ceramics such as Ni-ferrite, the high-energy flux in the range of 1500-2500 kW/m(2) is absorbed by an excess Frenkel defect formation. This non-equilibrium state defect is generated not by heating at a low heating-rate (30 K/min), but by irradiating high flux energy of concentrated solar beam rapidly at a high heating rate (200 K/min). The defect can be spontaneously converted to chemical energy of a cation-excess spinel structure (reduced-oxide form) at the temperature around 1773 K. Thus, the O(2) releasing reaction (α-O(2) releasing reaction) proceeds in two-steps; (1) high flux energy of concentrated solar beam absorption by formation of the non-equilibrium Frenkel defect and (2) the O(2) gas formation from the O(2-) in the Frenkel defect even in air atmosphere. The 2nd step proceeds without the solar radiation. We may say that the 1st step is light reaction, and 2nd step, dark reaction, just like in photosynthesis process.  相似文献   

2.
Environmental Science and Pollution Research - There has been growing interest in studying the relationship between energy strategies (energy efficiency and energy diversity) and economic growth to...  相似文献   

3.
Environmental Science and Pollution Research - The operation in energy arbitrage markets is an attractive possibility to energy storage systems developers and owners to justify an investment in...  相似文献   

4.
Hammarström L  Kullander S 《Ambio》2012,41(Z2):101-102
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5.
Environmental Science and Pollution Research - To understand the nexus between economic growth and energy sources, in this study, we have selected Pakistan and collected data over the period...  相似文献   

6.
Environmental Science and Pollution Research - The demand for energy has continued to increase because of global economic development, which has led to rising fuel prices and continued pollution...  相似文献   

7.
Municipal and state regulations limiting the allowable sulfur content of fossil fuels are having the effect of changing fuel use patterns of many of the nation’s utilities. The utility companies are faced with increased costs of lower sulfur fuels and capital expenditures associated with the fuel changes, as well as with greater uncertainty concerning long term supplies of suitable fuels. Capital costs for air pollution control are mounting. Electrostatic precipitators must be built to meet more stringent air pollution codes, and stack heights may have to be increased to improve discharge patterns. Other capital expenditures for added requirements such as steam and electric tracing and pumping equipment must be made to accommodate distinctive characteristics of low sulfur fuels. Air pollution control costs do not result in increased productivity, improved products, or products that will command a better price in the market. Nevertheless, the expenditures are essential. Nuclear power is the long range solution to which many utilities look but, in the shorter view, the power industry must expect continued cost increases in the areas of fuel and operating expenses, capital expenditures and research and development.  相似文献   

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Households consume more energy embodied in goods and services than they consume with energy carriers. Thus, energy assessments need to address both direct consumption and indirect consumption via commodities. This paper first presents a conceptual framework for describing and analysing the direct and indirect energy use of households. The framework is based on material flux analysis and differentiates between four household activities feeding, housing, transporting and consuming. Secondly, Swiss data on household energy consumption are presented and discussed in the context of household size, technology and consumption behaviour. It is shown that these factors considerably shape per capita energy demand. The third part presents energy projections based on trend assumptions for demographic and technological developments for the next 30 years. When zero growth per capita in commodities consumption is assumed, overall energy demand will increase by about 5%, mainly due to strong increases in gasoline demand. When the growth rate of commodities consumption exceeds 0.3% per year, embodied energy demand will offset efficiency gains achieved by technological improvements in the economic and domestic sectors and will fuel overall energy growth.  相似文献   

10.
Environmental Science and Pollution Research - Conventional energy consumption such as coal, natural gas, and oil is a source of deteriorating environmental sustainability as well as a severe...  相似文献   

11.
E.E. Kwon  H. Yi  H.H. Kwon 《Chemosphere》2013,90(4):1508-1513
This work showed that sewage sludge could be a strong candidate for biodiesel production. High lipid content (18–20%) with C16?18-carbon range was experimentally identified and measured. These lipids from sewage sludge were converted into biodiesel via the transesterification reaction with MgO–CaO/Al2O3 derived from magnesium slag, and biodiesel conversion was ~98%. The experimental work enabled explaining that temperature is the main driving force for the transesterification reaction, which can be enhanced in the presence of CO2. This also enables combination of esterification of free fatty acids and transesterification of triglycerides into a single process within 1 min in the temperature range of 350–500 °C. Sewage sludge residue after extracting lipids was also a good feedstock for recovering energy via thermo-chemical processes. The impact of CO2 co-feed on the pyrolysis/gasification process of SS residue was also investigated in this work. The CO2 injected into the thermo-chemical process remarkably increased the generation of CO by a factor of 2. Moreover, the introduction of CO2 into the pyrolysis/gasification process enabled reducing condensable hydrocarbons (tar) by expediting cracking; thus, utilizing CO2 as chemical feedstock for the gasification process not only leads to higher thermal efficiency but also has environmental benefits.  相似文献   

12.
Environmental Science and Pollution Research - The goal of this paper is to identify, for the first time, the role of solar production in driving silver prices. The empirical analysis makes use of...  相似文献   

13.
Solar energy conversion into electricity by photovoltaic modules is now a mature technology. We discuss the need for materials and device developments using conventional silicon and other materials, pointing to the need to use scalable materials and to reduce the energy payback time. Storage of solar energy can be achieved using the energy of light to produce a fuel. We discuss how this can be achieved in a direct process mimicking the photosynthetic processes, using synthetic organic, inorganic, or hybrid materials for light collection and catalysis. We also briefly discuss challenges and needs for large-scale implementation of direct solar fuel technologies.  相似文献   

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Environmental Science and Pollution Research - The present study seeks to investigate the sector-level energy consumption of oil and natural gas and to explore the linkage between economic growth,...  相似文献   

16.
Environmental Science and Pollution Research - Economic policy uncertainty has increased throughout the world since the previous few decades. Moreover, economic policy uncertainty significantly...  相似文献   

17.
Environmental Science and Pollution Research - The energy sector of Argentina is predominantly reliant on fossil fuels. Consequently, such fossil fuel dependency within the nation’s power...  相似文献   

18.
Environmental Science and Pollution Research - While the independent effect is widely examined, the joint effect of financial development and renewable energy on energy consumption has largely been...  相似文献   

19.
运用LCA技术可从全过程的视角识别和比较不同城市污水处理工艺在其生命周期各个阶段的能耗,并在此基础上提出改善其能效的措施。运用LCA方法对AB活性污泥法处理系统从其原材料开采和加工开始直到污水厂施工建设、处理运行以及废弃拆除的LC全过程能耗进行了识别和量化分析,并与普通活性污泥法进行了平行对照。研究结果表明,AB法的LC能耗在微孔和穿孔管两种曝气条件下可双普通活性污泥法分别节省9.5%和15.8%,但由于污水中有机物大部分转化为污泥形态,其比能耗仅与普通活性污泥法相当。AB法处理系统污泥的稳定化处理已成为提高其能效的重要途径。  相似文献   

20.
Globally, 1.3 billion on-road vehicles consume 79 quadrillion BTU of energy, mostly gasoline and diesel fuels, emit 5.7 gigatonnes of CO2, and emit other pollutants to which approximately 200,000 annual premature deaths are attributed. Improved vehicle energy efficiency and emission controls have helped offset growth in vehicle activity. New technologies are diffusing into the vehicle fleet in response to fuel efficiency and emission standards. Empirical assessment of vehicle emissions is challenging because of myriad fuels and technologies, intervehicle variability, multiple emission processes, variability in operating conditions, and varying capabilities of measurement methods. Fuel economy and emissions regulations have been effective in reducing total emissions of key pollutants. Real-world fuel use and emissions are consistent with official values in the United States but not in Europe or countries that adopt European standards. Portable emission measurements systems, which uncovered a recent emissions cheating scandal, have a key role in regulatory programs to ensure conformity between “real driving emissions” and emission standards. The global vehicle fleet will experience tremendous growth, especially in Asia. Although existing data and modeling tools are useful, they are often based on convenience samples, small sample sizes, large variability, and unquantified uncertainty. Vehicles emit precursors to several important secondary pollutants, including ozone and secondary organic aerosols, which requires a multipollutant emissions and air quality management strategy. Gasoline and diesel are likely to persist as key energy sources to mid-century. Adoption of electric vehicles is not a panacea with regard to greenhouse gas emissions unless coupled with policies to change the power generation mix. Depending on how they are actually implemented and used, autonomous vehicles could lead to very large reductions or increases in energy consumption. Numerous other trends are addressed with regard to technology, emissions controls, vehicle operations, emission measurements, impacts on exposure, and impacts on public health.

Implications: Without specific policies to the contrary, fossil fuels are likely to continue to be the major source of on-road vehicle energy consumption. Fuel economy and emission standards are generally effective in achieving reductions per unit of vehicle activity. However, the number of vehicles and miles traveled will increase. Total energy use and emissions depend on factors such as fuels, technologies, land use, demographics, economics, road design, vehicle operation, societal values, and others that affect demand for transportation, mode choice, energy use, and emissions. Thus, there are many opportunities to influence future trends in vehicle energy use and emissions.  相似文献   


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